2x100 jumps, efficiency on the springs, and bottom hammer on pies, have added a significant amount of points to the "level averages". Like George said, most of these people have been playing at least 5 years; Robbie and John really showed the effect of these techniques on consistent scoring and the leaderboard is now reflecting that, as the elite players incorporate the newest refinements. Don't be surprised to see another 3 or more players do it soon; Dean, Wes and Phil Tudo are all easy contenders.
tl;dr circus jumps, spring leaching and gambol pushed up the level averages in general, and the best players (new and old) did something with the knowledge.